Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Category
Sedimentary (Fossilized Organic Matter)
Browse sedimentary (fossilized organic matter) specimens identified by the Rock Identifier community.
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
mineral
Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)
SiO₂ (silicon dioxide)
Sedimentary
Baltic Amber (Butterscotch or Egg Yolk Variety)
Fossilized Tree Resin (Succinite); Approximate formula: C10H16O
Organic Gemstone (Succinite)
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Sedimentary
Amber
Succinite (organic mineraloid); Chemical formula: C10H16O
mineral
Kambaba Jasper (Crocodile Jasper)
Stromatolite (Fossilized Algae within Microcrystalline Quartz), SiO2
sedimentary
Petoskey Stone
Hexagonaria percarinata
sedimentary
Petoskey Stone
Hexagonaria percarinata
sedimentary
Petrified Wood
Silicified Wood (SiO2)
Mineral / Fossil
Pearl (in a decorative hair comb setting)
Calcium carbonate (CaCO3) primarily as Aragonite, bonded with Conchiolin
Organic Mineraloid
Chert / Flint
Chert (varietal name for microcrystalline quartz). Chemical formula: SiO₂
Mineral
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sedimentary or Metamorphic (low grade)
Limestone (Flagstone)
Fossiliferous Limestone (CaCO3)
sedimentary
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Sedimentary or Metamorphic (low-grade)
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
sedimentary
Spinosaurus Tooth
Spinosaurus aegyptiacus (fossilized in Hydroxyapatite)
sedimentary
Fossilized Brachiopod
Brachiopoda (Class Rhynchonellata or Spiriferida)
sedimentary
Horn Coral Fossil
Rugosa (extinct order of solitary corals)
sedimentary
Tree Agate
Dendritic Chalcedony (SiO2)
sedimentary
Fossilized Rugose Coral (Petoskey Stone precursor)
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Red Ochre (Hematite-rich Clay)
Limonitic/Hematitic Claystone (Fe2O3 with clay minerals)
Sedimentary
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Fossilized Coral (Petoskey Stone or similar)
Hexagonaria percarinata (Order: Rugosa)
sedimentary
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
metamorphic
Sandstone (Quartz Sandstone)
Arenite (primarily SiO2)
sedimentary
Chert (specifically Flint or Dark Chert)
Chert (SiO2)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
sedimentary
Moss Agate
Chalcedony (Silicon Dioxide with inclusions) - SiO2
mineral
Quartz Vein in Pelite (Metamorphic Rock)
Hydrothermal Quartz Veining in Metasedimentary Rock (SiO2)
metamorphic
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Organic Gemstone (Sedimentary classification)
Petoskey Stone
Hexagonaria percarinata
sedimentary
Mammoth Tooth Fragment
Mammuthus primigenius (fossilized dentin and enamel)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Sandstone
Arenite
sedimentary
Red Shale
Lutite (primarily composed of Hydrous Aluminum Silicates with Hematite staining)
sedimentary
Belemnite Fossil
Belemnitida (extinct order of Cephalopods)
sedimentary
Megalodon Shark Tooth Fossil
Otodus megalodon (fossilized in sedimentary matrix)
sedimentary
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Geode (Unopened)
Silica Concretion / Geode (Formula: SiO2 for quartz internal contents)
sedimentary
Sandstone (Ferruginous)
Arenite (Fe-rich)
sedimentary